The present invention relates to a device for regulating the passage of energy through a light-transmitting area, comprising a first polarization layer, a second polarization layer and a switching layer which is arranged between the two polarization layers and changes the polarization properties of polarized light as a function of temperature, where the two polarization layers are characterized by a suitable choice of their transmission in the transmission direction and their degree of polarization. The invention furthermore relates to a process for the production of the device according to the invention and to the use of the device for influencing light transmission and/or the passage of energy into an interior as a function of temperature.